Various machinery, such as engines, pumps, and turbines, employ components that transmit the load between the solid parts that are in relative motion. Common examples are piston rings, cams, gear teeth, and (of course) bearings. Often, these components are lubricated by maintaining an oil film between the two solid parts to minimize the friction and wear. In this blog post, we look at methods for modeling the fluid friction in lubricated joints.

When working with multibody systems, you may need to model a mechanism that transfers motion from one component to another. The mechanism used to implement this behavior, known as a cam-follower mechanism, plays an important role in many applications, including internal combustion engines, printing control mechanisms, textile weaving machines, and valves. You can easily model this type of mechanism with the Cam-Follower feature in the COMSOL® software. Let’s take a look at this feature in detail.

The trebuchet is a large siege weapon that you might recognize from movies set in the Middle Ages or fantasy worlds. This weapon is built on the idea of converting potential energy into kinetic energy to hurl a projectile over a large distance. Simple as it seems, the trebuchet is a complicated dynamical system. In this blog post, we will build a simplified model of a counterweight trebuchet using the Multibody Dynamics Module and examine some of its design features.

In the 1800s, two scientists — Nikola Tesla and Galileo Ferraris — separately invented their own versions of AC induction motors. Such AC motors turned out to be reliable alternatives to the DC motors that were popular at the time. To accurately study induction motors, we must account for the multiple physics that occur. As today’s example illustrates, we can include the electromechanical effects using the COMSOL Multiphysics® software.

When performing a noise, vibration, and harshness (NVH) analysis of a transmission system, the elasticity of the gear mesh plays a crucial role in obtaining useful results. To help you create an accurate gear simulation, new features and functionality in the COMSOL Multiphysics® software enable you to evaluate gear mesh stiffness. Today, we’ll explain why it’s important to account for gear mesh elasticity as well as how to compute and include gear mesh stiffness in your multibody dynamics model.

If you’ve ever gone on a road trip, you know that it’s a bit of a pain — literally. Part of why your body aches after driving long distances is due to whole body vibration (WBV), which can cause fatigue; motion sickness; and, eventually, serious health problems. To design systems that reduce WBV for cars and other applications, engineers need an efficient way to visualize the effect of vibrations on the human body. That’s where simulation comes in.

When a car hits a pothole, the suspension system can take on major damage in a matter of seconds. Suspension systems must be able to adapt to myriad road conditions while supporting the wheels, seats, and body of the car. To study the performance of a vehicle suspension system, you can use multibody analyses and a simplified lumped model of a mechanical system.

Gears are used in a variety of applications, such as clocks, industrial machinery, music boxes, bicycles, and automobiles. A gearbox is a major source of vibration and noise irrespective of how it is used. The most effective approach to reduce the noise radiation from a gearbox is to perform a vibroacoustic analysis to improve the design. Let’s see how the COMSOL Multiphysics® software can be used to help build quieter transmission systems.

When designing multibody systems, interconnected flexible and rigid bodies must be analyzed to see how they are affected by large rotational and translational displacements. While we can achieve this with the Multibody Dynamics Module in the COMSOL Multiphysics® software, we first want to confirm the reliability of the simulation results. Here, we discuss a benchmark model of a four-bar mechanism that helps prove the validity of these multibody dynamics simulations.

To accurately simulate a gear and obtain useful results, it is important to consider a number of elements behind the device’s design and how they are modeled. New features and functionality in the COMSOL Multiphysics® software provide you with the tools to address such properties and thus advance the reliability of your simulation studies. Today, we’ll review the various elements of gear modeling and explain how to account for them in our modeling processes.